Implement iterative precopy migration for Containers (Docker, Podman)

Question

I am implementing iterative precopy migration for containers (Docker, Podman) using the following commands:

sudo podman container checkpoint -R -e="/home/rohan/Desktop/Precopy migration/checkpoints/cp1.tar.gz" source2

sleep 1 sudo podman container checkpoint -R --pre-checkpoint -e="/home/rohan/Desktop/Precopy migration/checkpoints/predump1.tar.gz" source2

sleep 1

sudo podman container checkpoint -R -P -e="/home/rohan/Desktop/Precopy migration/checkpoints/predump2.tar.gz" source2

sleep 1

sudo podman container checkpoint -R -P -e="/home/rohan/Desktop/Precopy migration/checkpoints/predump3.tar.gz" source2

sleep 1

sudo podman container checkpoint --with-previous -R -e "/home/rohan/Desktop/Precopy migration/checkpoints/wpev3.tar.gz" source2

sleep 1

However, all the checkpoints are the same size (73.9 MB). I need the new checkpoints to capture only the dirty memory or changes since the last checkpoint or predump. What am I doing wrong? (https://i.sstatic.net/M0uULNpB.png)

Answer 1

check The link below

https://docs.podman.io/en/latest/markdown/podman-container-checkpoint.1.html#pre-checkpoint-p

"" --leave-running, -R Leave the container running after checkpointing instead of stopping it. The default is false.

--pre-checkpoint, -P Dump the container’s memory information only, leaving the container running. Later operations supersedes prior dumps. It only works on runc 1.0-rc3 or higher. The default is false.

The functionality to only checkpoint the memory of the container and in a second checkpoint only write out the memory pages which have changed since the first checkpoint relies on the Linux kernel’s soft-dirty bit, which is not available on all systems as it depends on the system architecture and the configuration of the Linux kernel. Podman verifies if the current system supports this functionality and return an error if the current system does not support it. ""